Just in case you still had any doubts on how important is the iPhone to Apple, 9to5mac put together this very informative and self-explaining chart of Apple's revenue.
As you can see, iPhone sales are by far Apple's most important business. In terms of revenue first, but it's safe to say that the iPhone is also Apple's most central product when it comes to its image, exposure, future and so on. Does this mean that the Mac will be left behind? No, but the iPhone is Apple's new locomotive, and we just can't wait to see how the iPad fits in there.